title: A new definition for an old entity: improved definition of mitral valve prolapse using three-dimensional echocardiography and color-coded parametric models.
abstract: BACKGROUND
  Differentiating between mitral valve (MV) prolapse (MVP) and MV billowing (MVB) on two-dimensional echocardiography is challenging. The aim of this study was to test the hypothesis that color-coded models of maximal leaflet displacement from the annular plane into the atrium derived from three-dimensional transesophageal echocardiography would allow discrimination between these lesions.
  
  
  METHODS
  Three-dimensional transesophageal echocardiographic imaging of the MV was performed in 50 patients with (n = 38) and without (n = 12) degenerative MV disease. Definitive diagnosis of MVP versus MVB was made using inspection of dynamic three-dimensional renderings and multiple two-dimensional cut planes extracted from three-dimensional data sets. This was used as a reference standard to test an alternative approach, wherein the color-coded parametric models were inspected for integrity of the coaptation line and location of the maximally displaced portion of the leaflet. Diagnostic interpretations of these models by two independent readers were compared with the reference standard.
  
  
  RESULTS
  In all cases of MVP, the color-coded models depicted loss of integrity of the coaptation line and maximal leaflet displacement extending to the coaptation line. MVB was depicted by preserved leaflet apposition with maximal displacement away from the coaptation line. Interpretation of the 50 color-coded models by novice readers took 5 to 10 min and resulted in good agreement with the reference technique (κ = 0.81 and κ = 0.73 for the two readers).
  
  
  CONCLUSIONS
  Three-dimensional color-coded models provide a static display of MV leaflet displacement, allowing differentiation between MVP and MVB, without the need to inspect multiple planes and while taking into account the saddle shape of the mitral annulus.
authors.affiliation: University of Chicago, Chicago, Illinois.
authors.forename: Karima
authors.initials: K
authors.lastname: Addetia
authors.affiliation: University of Chicago, Chicago, Illinois.
authors.forename: Victor
authors.initials: V
authors.lastname: Mor-Avi
authors.affiliation: University of Chicago, Chicago, Illinois.
authors.forename: Lynn
authors.initials: L
authors.lastname: Weinert
authors.affiliation: Philips Medical Systems, Andover, Massachusetts.
authors.forename: Ivan S
authors.initials: IS
authors.lastname: Salgo
authors.affiliation: University of Chicago, Chicago, Illinois. Electronic address: rlang@medicine.bsd.uchicago.edu.
authors.forename: Roberto M
authors.initials: RM
authors.lastname: Lang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D003116:Color; D003198:Computer Simulation; D019560:Echocardiography, Three-Dimensional / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D008945:Mitral Valve Prolapse / Q000000981:diagnostic imaging*; D015233:Models, Statistical; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D009626:Terminology as Topic
keywords: 2D; 3D; Billowing; MR; MV; MVB; MVP; Mitral regurgitation; Mitral valve; Mitral valve billowing; Mitral valve prolapse; Prolapse; TEE; Three-dimensional; Three-dimensional echocardiography; Transesophageal echocardiographic; Two-dimensional